Abstract
Mixed gas corrosion testing is used to simulate corrosion damage of electrical contacts. As a result of the demand for lower cost while maintaining high reliability, the testing conditions should be optimized to avoid overquality. Accordingly, we have determined the optimum exposure time in testing by comparing the corrosion damage on contacts exposed to mixed gas with that of field exposure. The maximum corrosion damage on the contacts was evaluated by extreme-value statistics. The optimum exposure time in testing is determined to be 10 hours for 10 years field exposure. The gas and moisture penetrate into plastic housing in which the contacts are placed. And the diffusion analysis of moisture in the plastic housing shows that the testing must be performed without the housing. Furthermore, we have designed a method for assessing the corrosion severity of the field environment. The method has been applied at two different fields.
